Solar thermal aerogel receiver and materials therefor

Patent metadata

Field	Value
Publication number	US-10889501-B2
Application number	US-201716079172-A
Country	US
Kind code	B2
Filing date	Feb 24, 2017
Priority date	Feb 24, 2016
Publication date	Jan 12, 2021
Grant date	Jan 12, 2021

Abstract

A silica aerogel having a mean pore size less than 5 nm with a standard deviation of 3 nm. The silica aerogel may have greater than 95% solar-weighted transmittance at a thickness of 8 mm for wavelengths in the range of 250 nm to 2500 nm, and a 400° C. black-body weighted specific extinction coefficient of greater than 8 m 2 /kg for wavelengths of 1.5 μm to 15 μm. Silica aerogel synthesis methods are described. A solar thermal aerogel receiver (STAR) may include an opaque frame defining an opening, an aerogel layer disposed in the opaque frame, with at least a portion of the aerogel layer being proximate the opening, and a heat transfer fluid pipe in thermal contact with and proximate the aerogel layer. A concentrating solar energy system may include a STAR and at least one reflector to direct sunlight to an opening in the STAR.

First claim

What is claimed is:

1. A solar thermal aerogel receiver comprising:
an opaque frame defining an opening;
an aerogel layer disposed in the opaque frame, with at least a portion of the aerogel layer being disposed proximate the opening; and
a heat transfer fluid pipe in thermal contact with and proximate the aerogel layer.

2. The solar thermal aerogel receiver of claim 1 , wherein the aerogel layer comprises silica aerogel.

3. The solar thermal aerogel receiver of claim 2 , wherein the silica aerogel defines a porous material with pores having a mean radius of less than 5 nm with a standard deviation of 3 nm.

4. The solar thermal aerogel receiver of claim 1 , wherein the aerogel layer comprises an absorber layer.

5. The solar thermal aerogel receiver of claim 1 , wherein the aerogel layer comprises silica aerogel having (i) greater than 95% solar-weighted transmittance at a thickness of 8 mm for wavelengths selected from the range of 250 nm to 2500 nm; and (ii) a 400° C. black-body weighted specific extinction coefficient of greater than 8 m 2 /kg for wavelengths selected from the range of 1.5 μm to 15 μm.

6. The solar thermal aerogel receiver of claim 5 , wherein the opaque frame further comprises an insulating layer.

7. The solar thermal aerogel receiver of claim 1 , wherein the heat transfer fluid pipe comprises a black absorber layer.

8. The solar thermal aerogel receiver of claim 1 further comprising a transparent outer layer disposed in the opening in the opaque frame.

9. The solar thermal aerogel receiver of claim 8 , wherein the transparent outer layer comprises at least one of glass and a transparent polymer.

10. The solar thermal aerogel receiver of claim 8 , wherein the transparent outer layer forms at least a portion of a flat bottom surface of the opaque frame.

11. The solar thermal aerogel receiver of claim 8 , wherein the aerogel layer is in direct contact with the transparent outer layer.

12. The solar thermal aerogel receiver of claim 8 , wherein the transparent outer layer and the aerogel layer define an air gap therebetween.

13. The solar thermal aerogel receiver of claim 1 , wherein the receiver has a maximum solar-to-exergy conversion efficiency of greater than 35% at an optical concentration of 40 suns.

14. A concentrating solar energy system comprising:
a solar thermal aerogel receiver comprising:
an opaque frame defining an opening,
an aerogel layer disposed in the opaque frame, with at least a portion of the aerogel layer being disposed proximate the opening, and
a heat transfer fluid pipe in thermal contact with and proximate to the aerogel layer; and

at least one reflector configured to direct sunlight to the opening.

15. The concentrating solar energy system of claim 14 , wherein the aerogel layer comprises an absorber layer.

16. The concentrating solar energy system of claim 14 , wherein the aerogel layer comprises silica aerogel.

17. The concentrating solar energy system of claim 16 , wherein the silica aerogel defines a porous material with pores having a mean radius of less than 5 nm with a standard deviation of 3 nm.

18. The concentrating solar energy system of claim 14 , wherein the aerogel layer comprises silica aerogel having (i) greater than 95% solar-weighted transmittance at a thickness of 8 mm for wavelengths selected from the range of 250 nm to 2500 nm; and (ii) a 400° C. black-body weighted specific extinction coefficient of greater than 8 m 2 /kg for wavelengths selected from the range of 1.5 μm to 15 μm.

19. The concentrating solar energy system of claim 14 , wherein the heat transfer fluid pipe comprises a black absorber layer.

20. The concentrating solar energy system of claim 14 , wherein the opaque frame further comprises an insulating layer.

21. The concentrating solar energy system of claim 14 , wherein the solar thermal aerogel receiver has a maximum solar-to-exergy conversion efficiency of greater than 35% at an optical concentration of 40 suns.

22. The concentrating solar energy system of claim 14 further comprising a transparent outer layer disposed in the opening.

23. The concentrating solar energy system of claim 22 , wherein the transparent outer layer comprises at least one of glass and a transparent polymer.

24. The concentrating solar energy system of claim 22 , wherein the aerogel layer is in direct contact with the transparent outer layer.

25. The concentrating solar energy system of claim 22 , wherein the transparent outer layer and the aerogel layer define an air gap therebetween.

26. The concentrating solar energy system of claim 22 , wherein the transparent outer layer forms at least a portion of a flat bottom surface of the opaque frame.

Assignees

• Massachusetts Inst Technology

Inventors

• Chen Gang
• Wang Evelyn N
• Boriskina Svetlana
• Weinstein Lee A
• Yang Sungwoo
• Bhatia Bikramjit S
• Zhao Lin
• Strobach Elise M
• Cooper Thomas A
• Bierman David M
• Huang Xiaopeng
• Loomis James

Classifications

• C04B14/064

  Silica aerogel · CPC title

• C01B33/1585 Primary

  Dehydration into aerogels · CPC title

• F24S2023/872

  Assemblies of spaced reflective elements on common support, e.g. Fresnel reflectors · CPC title

• F24S70/20

  characterised by absorbing coatings; characterised by surface treatment for increasing absorption · CPC title

• F24S80/56

  characterised by means for preventing heat loss · CPC title